I had not used the MM for about a month, I went to fire it up and the MM shows 4 white lights, but does not turn on. I have tried 3 batteries with the same result.
Any ideas how to remedy this?

Hi there, just a silly reminder, the startup method is short press once and then press again and hold to turn on the drone. Could you please provide a short video of the issue for further confirmation?

Hi DJI Thor, problem fixed, On button was sticking, a bit jiggling and all is good now, I will monitor the situation. If it happens again I will put a ticket into support.